1. Field of the Invention
This invention relates primarily to electromechanical circuits for use in models and toys. More particularly, it relates to such circuits which are able to produce light, sound and similar effects comparable to those which can be produced by use of more complex electronic circuitry. Most especially, it relates to such circuits in which current or voltage modulation or both, produced by operation of an electric motor, are used to produce light, sound and similar effects.
2. Description of the Prior Art
It is known in the art to employ various electronic circuits for the purpose of producing flashing lights, sirens, and other sound effects in toys and models. For example, the commercially available LM3909 Flasher/Oscillator Circuit obtainable from National Semiconductor Corporation, Santa Clara, Calif., can be used for this purpose. Since such toys and models usually have considerably more market appeal if they incorporate motion as well, some form of a motor circuit is typically provided to produce the motion.
While great progress has been made in providing such circuits as the LM3909 on a high volume, low cost basis, it would be advantageous if it was possible to obtain light, sound and smilar effects without the provision of a separate electronic circuit for this purpose. While this can be achieved to some extent through use of cam-actuated contacts driven by the same motor that provides motion in the toy or model, it is difficult to provide enough variation in the effects produced by this method to give a realistic enough combination of effects. Consequently, that approach alone will not produce substantial cost savings when compared to the cost of providing the same effects with a separate electronic circuit. Toy and model manufacturers have therefore continued their efforts to provide these effects on a more cost effective basis.